For the last 3 years it's been about every 13 months, but this time we've been propelled to a "new level" in USD terms. I wouldn't be terribly surprised if we averaged $1-$3 UNO for the first 3 years, $3-5 for the next, etc. Lots of drifting downward and spikes upward along the way, but gradually a long-term picture materializes.

"Patience is a virtue"